While big-budget western game franchises often stand accused of design-by-focus-group, their Japanese counterparts are still dominated by mercurial auteurs with singular – and often bizarre – visions.

Legendary figures such as Nintendo designer Shigeru Miyamoto, Dark Souls’ Hidetaka Miyazaki, Metal Gear Solid’s Hideo Kojima and Ico’s Fumito Ueda are inextricably linked with the blockbuster titles they helped to create, in a way few western designers are.

Yoko Taro, the driving force behind 2010’s Nier (rarely seen in public without a giant mask), has a rightful place on that list. His genre-bending JRPG became a cult classic despite receiving a fraction of the marketing push of better known franchises. Part action brawler, part narrative-heavy RPG, part top-down bullet-hell, Nier defied categorisation. Seven long years later, this sequel is every bit as thrilling, endearing and unhinged as the first.

Set thousands of years after the events of the first game, it follows female android 2B, who is sent on a mission to earth to investigate the alien race that forced mankind to flee to the moon. Here she encounters a host of adorable, aggressive machines designed to destroy anything humanoid.

The story is heavily inspired by classic anime, with shades of Neon Genesis Evangelion’s coming-of-age angst and a big dose of Ghost in the Shell’s Cartesian dualism. There are also nods to the original game’s convoluted plot, but newcomers shouldn’t worry: they’ll be just as confused as everybody else.

As in the first instalment, the action is fast-paced and unpredictable. You might be experiencing the world as a free-roaming, third-person RPG when the camera suddenly drags itself from your control and spins to create a side-scrolling platformer, or a top-down shooter, forcing you to adapt second-by-second. The combat is joyously bonkers – with no stamina bar to worry about, you can concentrate on chaining together attacks with your ludicrously oversized arsenal, juggling melee attacks with fire support from your floating robot accomplice.

This all takes place in a gorgeous, if slightly hackneyed, post-apocalyptic world where nature has reclaimed the decaying remains of human cities. Even the lack of finesse – there are frequent areas where your character runs into invisible walls, for instance – somehow adds to the eccentric charm.

It isn't all positive, though. The English voice acting is at best average and at worse lamentable (I strongly advise switching to the original Japanese with subtitles), and the cut-scenes are something to endure rather than enjoy. Boss fights, meanwhile – a regular occurrence, each one gargantuan, as is de rigueur for the genre – tend to be protracted affairs, most of which could benefit from cutting far sooner to the chase. Stray too far from the main story, meanwhile, and you'll soon get bogged down in the worst kind of busy-work: dozens of tonally identical fetch quests and uninspired escort missions, which feel hopelessly out of place in a game that makes a genuine stab at doing things differently.

Also problematic is the queasy fetishisation of the female characters, all of whom are essentially sex-doll androids wearing goth-lolita bondage gear. We meet 2B crotch-first and this largely sets the tone for the rest of the game. There’s also an attempt to explore sex in a more intelligent way, asking how humanity might be affected should the invention of androids remove the need for reproduction (one striking scene shows rusting tin men joylessly emulating intercourse while chanting “Love, love, love”). But the fact so long has been spent meticulously animating 2B’s naked buttocks so you can admire them as she’s climbing a ladder suggests this game is not up to pondering the great sexual questions of our age (it's no coincidence that a pre-release controversy centred around whether Nier's designers had given 2B a lifelike anus – rumours Taro gleefully encouraged).

It's a shame, because when those animation skills are put to good use, they really shine. 2B has the sassiest walk, and details like her parkour-bounce off ledges add physicality to this implausible world.

Nier: Automata doesn’t excel at any one thing, but it smashes together an embarrassment of ideas and comes up with something that exceeds the sum of its parts. Moreover, there’s a sense that you’re experiencing the unadulterated vision of a genuine video-game pioneer. Every narrative twist, every unexpected shift in perspective, every fourth wall-breaking interaction offers an insight into the mind of Yoko Taro, and those brain-folds are a wonderfully surreal place to explore.